The present invention relates to a dispenser for double-edge razor blades and particularly relates to a two-piece dispenser comprised of a cover and tray having constructional features which facilitate the plastic molding of the dispenser.
Dispensers for double-edge razor blades are well known in the art and are commercially successful. A typical double-edge razor blade dispenser is described and illustrated in U.S. Pat. No. 2,692,674. Such dispenser includes essentially two plastic molded parts, a cover and a tray. When the cover and tray are secured one to the other, they define a first or top dispensing compartment in which, prior to their assembly, a plurality of blades are disposed. The construction is such that the blades are conveniently dispensed alternately from the opposite ends of the dispenser. Also, there is provided a compartment along the underside of the tray for storing used razor blades, this second compartment having openings at either end for insertion of the used blades.
The cover and tray are conveniently secured one to the other by an interlocking rib and detent on the respective parts. For example, the tray may carry a laterally outwardly extending projection for reception in a corresponding groove along depending side flanges of the cover. Alternately, the cover may have depending flanges which carry laterally inwardly extending projections for receipt in one or more recesses formed along the sides of the tray. Also, to form the second compartment for the used blades, it is necessary to provide laterally inwardly projecting ledges or flanges or a complete bottom cover with openings at either end. It will be appreciated that such ledges or surface are closed by the upper surface of the tray.
Dispensers of this type are conventionally formed of a plastic molded material. In order to form the foregoing briefly described configurations, in each of the cover and the tray, it is essential that the mold parts have side actions. Thus, the mold parts require elements which move laterally of the mold parts, i.e., parallel to the parting line of the mold. For example, if the cover is provided with laterally inwardly extending flanges for detenting engagement with locking surfaces on the tray, the volume between the flanges and the top surface of the cover must be occupied during molding by a part which can be withdrawn sideways relative to the parting line of the mold. Otherwise, the molded cover cannot be removed from the mold. Likewise, the ledges or bottom surface of the tray heretofore cannot be formed without mold parts having this side action.
As is well recognized in the plastic molding industry, side action on molding machines increases the cycle time for molding the parts. A consequence of increased molding time is, of course, lower production rates for a given mold. It will be appreciated that dispensers for double-edge razor blades are manufactured in the millions and that, therefore, it is desirable to reduce the cycle time for molding the plastic parts whereby higher production rates can be achieved.
Additionally, the blades are alternately staggered in assembly. In most commercial dispensers, arrows are provided on the blades visible through the thumb window of the cover to indicate the direction in which the next blade will be removed from the dispenser. In certain assembly machines for disposing the blades in the dispenser, the tray is passed continuously in one direction under a series of blade feeders, one for each blade count. It is therefore important that the blades can be picked off from the feeders in an alternating sequence.
According to an aspect of the present invention, there is provided a cover and a tray for assembly into a dispenser for double-edge razor blades, the cover and tray being constructed to facilitate molding thereof of plastic material without mold parts which use any side action. To accomplish this, the present invention provides a dispenser, including a cover and a tray, which, when assembled, define as in the prior art, a first compartment for storing unused razor blades. A second compartment is provided in the tray for storing used razor blades. The cover is also provided with depending flanges for engaging along the sides of the tray, the flanges having laterally inwardly projections for engaging locking surfaces carried by the tray. However, in accordance with the present invention, the cover additionally is provided with a plurality of openings or windows respectively overlying and in registration with each of the laterally inwardly extending projections. The openings through the cover extend laterally and longitudinally distances at least corresponding to the lateral and longitudinal extents of the underlying projection. When forming the cover, a part of the fixed mold projects to form each opening or window and extends up to the interior surface of the laterally inwardly extending projection opposite the cover. The mold part is, of course, preferably tapered and the corresponding window will likewise be tapered. In this manner, the cover of the dispenser can be released from the fixed mold part by pushing the cover off the part or vice-versa, the taper of the mold part facilitating release of the cover. The mold part thus occupies the space between the locking surface of the projection and the interior surface of the cover yet does not inhibit or require side action of any part of the mold to form the cover or disengage the cover from the mold.
In a similar manner, the ledges on the bottom of the tray and which define in part the second compartment for storing used razor blades, may be formed without side action of mold parts. To accomplish this, the overlying surface of the tray which forms the upper surface of the used blade compartment (and also the underside of the unused blade compartment) is provided with openings or windows which overlie and lie in registry with the ledges. Thus, to form the ledges and the space between the ledges and the overlying surface, mold parts, preferably slightly tapered, project from the mold to form the openings and extend inwardly to occupy the area between the ledges and the upper surface. Thus, the tray can be removed from the mold without side action of any mold parts simply by pushing the tray unidirectionally off the mold or vice-versa.
Additionally, in accordance with another aspect of the present invention, there is provided a pair of openings along the longitudinal centerline of the dispenser and disposed in spaced relation one from the other on opposite sides of the lateral centerline of the dispenser. By providing such openings, a jig fixture may be used when loading the tray with razor blades. Thus, the fixtured tray would pass continuously in a single direction under a series of blade feeders and a fixture pin would project through the slots to pick off every other blade.
In a preferred embodiment according to the present invention, there is provided a dispenser for double-edge razor blades, comprising a tray and a cover overlying the tray, the tray and cover defining a first compartment for storing unused double-edge razor blades, and defining a blade outlet for dispensing blades from the compartment. Means are carried by the tray defining a second compartment for storing used blades, together with an opening for receiving used blades into the second compartment. The cover has depending side flanges for overlying opposite side faces of the tray, respectively, together with means defining a locking surface along each side of the tray. Each flange of the cover carries a laterally inwardly extending projection for engaging the locking surface on the corresponding side of the tray to secure the tray and cover one to the other. The cover has an opening therethrough on each of its opposite sides in registration with the underlying projection on the flange, the cover having a lateral extent at least corresponding to the lateral extent of projection.
In a still further preferred embodiment according to the present invention, there is provided a dispenser for double-edge razor blades, comprising a tray and a cover overlying the tray, the tray and the cover defining a first compartment for storing unused double-edge razor blades, and defining a blade outlet for dispensing blades from the compartment. Means are carried by the tray defining a second compartment for storing used blades, together with an opening for receiving used blades into the second compartment. The tray has a body portion extending substantially between the opposite ends and the opposite sides of the tray and a pair of laterally inwardly extending ledges are spaced laterally one from the other and spaced from the body portion to define at least in part with the body portion the second compartment. The body portion has a pair of openings accessible from the opposite side thereof from the ledges and in registration with the ledges, the latter openings each having a lateral extent at least corresponding to the lateral extent of its registering ledge.
Accordingly, it is a primary object of the present invention to provide a novel and improved dispenser for double-edge razor blades which can be readily and easily formed of plastic materials in molds without mold parts employing side action.
These and further objects and advantages of the present invention will become more apparent upon reference to the following specification, appended claims and drawings.